CVE-2021-3866

Public Exploit
Cross-site Scripting (XSS) - Stored in zulip/zulip

Description

Cross-site Scripting (XSS) - Stored in GitHub repository zulip/zulip more than and including 44f935695d452cc3fb16845a0c6af710438b153d and prior to 3eb2791c3e9695f7d37ffe84e0c2184fae665cb6.

Category

5.4
CVSS
Severity: Medium
CVSS 3.1 •
CVSS 3.0 •
CVSS 2.0 •
EPSS 1.00% Top 25%
Vendor Advisory zulip.com
Affected: zulip zulip/zulip
Published at:
Updated at:

References

Link Tags
https://huntr.dev/bounties/5f48dac5-e112-4b23-bbbf-cc00ba83bcf2 third party advisory exploit
https://github.com/zulip/zulip/commit/3eb2791c3e9695f7d37ffe84e0c2184fae665cb6 third party advisory patch
https://blog.zulip.com/2022/01/19/cve-2021-3866/ vendor advisory

Frequently Asked Questions

What is the severity of CVE-2021-3866?
CVE-2021-3866 has been scored as a medium severity vulnerability.
How to fix CVE-2021-3866?
To fix CVE-2021-3866, make sure you are using an up-to-date version of the affected component(s) by checking the vendor release notes. As for now, there are no other specific guidelines available.
Is CVE-2021-3866 being actively exploited in the wild?
It is possible that CVE-2021-3866 is being exploited or will be exploited in a near future based on public information. According to its EPSS score, there is a ~1% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
What software or system is affected by CVE-2021-3866?
CVE-2021-3866 affects zulip zulip/zulip.
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